Cloth towels and rags are commonly used in manufacturing and commercial environments for cleaning up liquids and particulates. Such woven materials are absorbent and effective in picking up particulates within the woven fibers of the material. After such towels and rags are used they are often laundered and reused. However, such woven materials have deficiencies. First, the woven structure of the cloth material makes it porous; liquids often penetrate through the cloth and can contact the hands of the user. This can be an inconvenience to the user as their hands may become dirty with the liquid they are trying to absorb with the towel or rag. Such fluid penetration often necessitates the use of multiple layers of cloth. Liquid or substances passing through the woven material can be dangerous to the user if the substance being cleaned up is a solvent, caustic material, hazardous chemical, or another similarly dangerous substance.
Secondly, even when such cloth towels and rags are laundered they often still contain residues or remnant metal particulate that can damage the surfaces that are subsequently contacted by such a towel or rag and may possibly injure the hands of the user. Finally, such cloth towels and rags often smear liquids, oils and greases rather than absorb them.
An alternative to cloth rags and towels are wipers made of pulp fibers. Although nonwoven webs of pulp fibers are known to be absorbent, nonwoven webs made entirely of pulp fibers may be undesirable for certain applications such as, for example, heavy duty wipers because they lack strength and abrasion resistance. In the past, pulp fiber webs have been externally reinforced by application of binders. Such high levels of binders can add expense and leave streaks during use which may render a surface unsuitable for certain applications such as, for example, automobile painting. Binders may also be leached out when such externally reinforced wipers are used with certain volatile or semi-volatile solvents.
Other wipers have been made that have a high pulp content which are hydraulically entangled into a continuous filament substrate. Such wipers can be used as heavy duty wipers as they are both absorbent and strong enough for repeated use. Additionally, such wipers have the advantage over cloth rags and towels of higher absorbency and less liquid passing through to the hands of the users. Examples of such materials that can be used in heavy duty wipers can be found in U.S. Pat. Nos. 5,284,703, 5,389,202 and 6,784,126, all to Everhart et al.
The embossing pattern present on such hydroentangled pulp wipers provides an embossed surface texture that aids in cleaning up and absorbing oils and greases along with particulates. However, when such wipers become wet from the liquids that they absorb, the embossing structure becomes less defined and worn. The effectiveness of the wiper is compromised and the wiper will smear any additional oils and greases that it then comes in contact.
There is a need for a hydroentangled fibrous nonwoven composite material that is absorbent, but will maintain its embossing structure in use, after the material becomes wet.